International Harvester Oddity

Part one of three: Restoring a 2 HP IHC Nonpareil

By Peter Rooke

| December 2006

The Nonpareil engine with round inspection hole and rounded crankcase.

After scouting around for a new project, word came of an
"Osborne" engine ripe for restoration. It was only being sold
because the owner was trying to raise money to purchase a rare
tractor. At that time, I had little knowledge of the engine's
history and thought I was being offered an ordinary International
Harvester. However, research on the Internet soon provided a lot of
background information.

Engine history

Osborne engines were manufactured by IHC while the company was
under investigation by the government for unfair trading. To get
around this dispute they marketed Nonpareil engines under the names
of Osborne and McCormick based on the Famous, and Titan engines
under the Deering banner. My Nonpareil engine, no. KG 671, was
manufactured in 1911, sold by Osborne and painted blue rather than
red.

There were a few small changes in the engine construction from
the Famous: It was lighter, the base casting had a rounded profile,
the hand plate (inspection cover) was round and the pipe-work
layout was different. In the case of my 2 HP engine, some
International Junior parts were used rather than those of the
standard 2 HP Famous, but I do not know if this was common practice
- it probably was.

My purchase

The engine was basically in bits as restoration of this engine
had already been started with new fuel and water pump pistons and
wrist pins. In addition, new castings had already been made from a
broken exhaust valve rocker and governor bracket. The cylinder head
and valves were rusted and clearly required work. The cylinder bore
was thick with grease and the piston appeared a reasonable fit, but
I was to discover later that there was excessive wear. There were
numerous pieces missing, the most important being the hand plate
with the engine details on it. I later managed to read the engine
number stamped on the end of the crankshaft.

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The Nonpareil engine with round inspection hole and rounded crankcase.

Turning the external dimensions of both bearings.

The puller arrangement through the crankcase to remove the main bearings (plug on LHS).

The engine and a box of “bits” back in the workshop.

The crankshaft and bearing showing the blue dye, partway through the scraping process.

The bearings on lathe to cut grease groove with the ground high speed steel cutter.

A finished bearing showing the grease grooves, resting on an old bearing shell.

Drilling for the valve sleeves.

The usty valve seats in the cylinder head.

Top of the cylinder head, with corroded valve and plastic metal repair to rocker.

The valve sleeves ready for fitting.

The new valves; the retaining nuts were changed later.

The rocker arm on the milling table for a skim cut to true it up. (As this was a light cut, Peter cheated and did not bother to change over to the milling chuck.)

The valve seats – one scraped and the other in original condition.

Ready to measure the piston ring gap. The end of the liner can be seen and the oil hole.

The cylinder showing the ridge from wear at the top of the stroke.

Fitting the second piston ring using shim stock. The clean up of skim cut on the piston skirt can be seen.

Turning the piston ring grooves using the ground high speed steel cutter.

Getting started

As a first step, I decided to try and locate another 2 HP
Nonpareil so I could copy the hand plate. If I managed to find
another engine I would have a source to check dimensions of other
missing parts. I placed a note in England's Stationary Engine
magazine but it drew no response. I heard through the grapevine
that there was an engine in Scotland. Undaunted, I decided to try
and track it down. I spent a few evenings telephoning the
secretaries of the engine clubs in Scotland and following up their
leads. Gradually, one trail started to prove interesting and my
hopes were raised when I was given the name of an enthusiast who
had apparently just sold such an engine. However, I was back to
square one when I spoke to him; he told me he had sold it 15 years
ago and had no idea of its whereabouts!

In May we went to the annual Victorian Extravaganza in
Llandudno, North Wales, and leaving my wife to go around the
stalls, I set off down the engine line taking photos and stopping
at every exhibit asking owners if they knew anyone with a
Nonpareil. Much to my surprise I was given a name and better yet a
telephone number, so I was anxious to get home and follow up this
lead. Initially my hopes were dashed when I telephoned; I was told
he had two Nonpariels, but not a 2 HP. However, when I told him I
wanted to copy the hand plate he said he had one hanging on the
wall and was happy to let me borrow it to get a casting made.
Unfortunately there was no engine that I could use for reference
purposes.

Bearings

The original bearings were badly worn, as were most working
parts of the engine. I was faced with two options - bore out the
bearings and line with white metal or make new ones. Not being too
skilled in pouring white metal, I decided to make new bearings and
my credit card took the strain as I ordered 8 inches of cored
leaded bronze. The literature I had by IHC on its gas engines
refers to phosphor bronze bearings, but I consider leaded bronze to
be more appropriate material for these slow revving engines.

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Before starting to make the bearings, I had to remove the old
ones to take measurements. After taking out the locking screws I
tried to push out the old bearings with a hammer and brass drift.
No joy. They were stuck fast.

Plan B was to make a plug to fit the bearing and then pull them
back into the crankcase using a threaded rod. This worked.

To machine the bearings, I drove a temporary plug into the core
of the leaded bronze, which I center drilled so the end of the
bronze could be supported by the tailstock during turning. From the
measurements of the old bearings, I turned the external dimensions
and shoulders for both bearings first and then parted off the
partially finished bearings.

To bore out the internal diameter, I mounted each bearing shell
in the 4-jaw chuck, and concentricity set and checked them using a
dial gauge. When I made the plug to remove the old bearings, I
machined two shoulders on it. One matched the diameter of the
crankshaft minus 0.0005-inch and one the exact diameter plus
0.0001-inch. I then used this as a gauge to ensure boring was
accurate.

After completing the internal bore, I removed the sharp edges on
the bearing shells with a file and used an old form tool to start
rounding the shoulder that would fit against the web of the
crankshaft. I checked the bearings on the crank for a good running
fit.

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I pressed the bearings into position and then drilled the grease
and oil-way holes inside the crankcase, plus drilled the dimples
for the retaining bolts with a small power drill. I took care to
ensure all swarf was removed from the bearings and crankcase. I
removed the bearings and set them on the lathe again to cut the
grease grooves to line up with the drilled grease hole. I cut these
by fitting a ground, high speed steel cutter, 0.010-inch wide, in
the boring bar and cutting the groove using the hand wheel on the
lathe saddle with the chuck locked in position. The final task to
fit the bearings was to profile the shoulder that touches the
crankshaft web. Having already removed some of the shoulder with a
form tool when machining, all it needed was the application of
engineer's blue to the crankshaft and a little repetitive work with
the scraper to ensure a good fit. I then pressed the new bearings
in place, taking care to ensure they were fit to the correct side
and the grease, oil holes and locking screw dimples aligned
correctly.

After I wiped it with light oil, the crankshaft was put in place
and the crankshaft bearing plate was fitted with an old gasket used
to check that there was sufficient side clearance and the
crankshaft moved freely. It was necessary to re-scrape one of the
bearing shoulders to achieve a good running fit.

I examined the big end bearing next and fit it around the big
end. I guess this had been replaced during the life of the engine,
as there was still plenty of metal - albeit badly scored with
uneven wear. I reduced the thickness of the shims by making some
thinner ones and scraped the bearing to a good, even fit in the
same manner as the main bearings.

The little end had already been replaced although it was a tight
fit for the new gudgeon pin. I reamed this to size using an
adjustable reamer.

Cylinder head

The photos clearly show the problems with the cylinder head -
worn valve seats, corroded threads for the water pipe and plugs,
and a broken rocker arm that had been repaired with plastic metal.
The photo of the underside shows the rust around the valve seats;
both valves needed replacement. Unlike the Famous engines, there
was no inlet valve lock plate to hold the inlet valve closed.

Valve sleeves

I made new valve sleeves first by turning some cast iron to an
external diameter of 0.502-inch and drilling an undersized hole for
the 3/8-inch valve stems that would be reamed to size when fitted.
The sleeves were made 2-1/2 inches long - slightly over length to
be reduced to size later.

I mounted the cylinder head on the table of the milling machine
and centered as accurately as possible over an existing valve stem
hole that was drilled out using increasingly bigger drills, up to
1/2-inch. Once I had drilled both stems out, the new sleeves were
coated in Loctite, pressed into position and trimmed to a flush
fit. Finally, I reamed them out to a diameter of 0.377-inch to
allow easy movement of the valves.

I made new valves by forming the valve heads out of 2-inch
diameter steel with a 3/8-inch hole in the center for the valve
stem, which I made out of 3/8-inch diameter silver steel as this
had an accurate diameter and needed no machining. I brazed the
stems into the new heads, which I cleaned and tapered the edge of
the valve 30 degrees, ready for lapping. I was unsure about the
length of the valve stem as the originals had been sawn off at some
stage and the top pieces were missing. I deliberately cut them
oversize to be trimmed later. I cut a 3/8-by-16 thread in the top
1-inch of the valve stem.

As can be seen from the photos, the valve seats were badly
corroded. Starting with a half round file I trued up the seats, and
when they were almost the right profile I applied engineer's blue
to the new valve heads. I repeatedly fitted and scraped the seats
until there was a solid ring of blue around the seat indicating a
good fit.

Once I fit the valve, I could then gauge the length of the stems
by fitting them in the head and cutting them until they were
slightly longer than the horizontal level of the exhaust rocker
arm. I had no idea about the style of the spring retaining nuts and
whether these nuts were locked in place by a pin through a hole in
the valve stem like the Famous engine or whether lock nuts were
used. Despite pleas for help in engine magazines and websites, I
had not received a reply from any owner of a 2 HP Nonpareil. The
cylinder head has the part number of an IHC Junior (GA 7088) and a
poor illustration in a parts list showed a top hat style nut.
Having made the nuts to the size I thought correct, I subsequently
traced another Nonpareil owner, Mike, in California who proved very
helpful. Not only did he provide several photos, but also some
measurements, which allowed me to make an accurate copy of the
valve nuts, which were slightly larger than my originals.

New valve rocker

The old exhaust rocker had broken at some stage and a temporary
repair had been made with plastic metal, perhaps so that it could
be used as a pattern to cast a replacement. I had a new one cast,
which I set on the table of the milling machine and trued up the
contact surfaces. I then drilled a 1/2-inch hole for the pivot pin
and a 3/8-inch hole for the pushrod bolt. I drilled a 3/32-inch
hole in the top of the pivot pinhole and chamfered it as an oiling
point for the pivot pin.

Removing plugs

The plugs used to block two of the waterway holes in the
cylinder head were badly corroded and it was impossible to tell if
they were watertight. They were probably fine, but to be on the
safe side while the engine was disassembled, and also to help
extract any rust in the head, I removed them. A little effort with
a large pipe wrench removed one, but the other stubbornly refused
to budge and I had to drill it out. I then tidied up the threads in
all three water holes with a 1/2-by-14 NPT tap. Rust had eroded a
lot of metal, but I planned to use gasket sealer around the threads
of the new blanking nuts and pipe work to achieve a good seal. I
hoped I would never need to remove them!

Cylinder/piston

The cylinder came with the bore coated in a thick layer of
grease. When I purchased it I tried the piston in the bottom of the
bore and it appeared tight enough. However, when I removed the
grease the full extent of the wear was apparent. While only a few
thousandths loose at the bottom, the bore opened by 0.070-inch just
below the combustion area.

Close examination of the piston also showed wear around the ring
grooves, particularly the top ring, where there was a taper and the
width of the groove was 0.035-inch oversize at the edge.

What should I do? I mulled over several solutions: I could get
the cylinder bored out by a machine shop 0.070-inch oversize and
make a new piston, sleeve the old piston or get the cylinder lined,
retaining the old piston. The first solution was attractive as I
could machine a new piston, but after further thought I decided to
take the plunge and get the cylinder sleeved, as I found a
commercial sleeve that would fit. It hurt me to pay someone else to
machine the block to fit it!

Of course this was not straightforward, as the machine shop
could not bore to the bottom of the cylinder without removing the
cylinder head studs, which I was reluctant to do in case I broke
one. However, as the wear at the bottom of the cylinder was small,
it was bored to within 1-inch of the bottom. This left a small step
of around 0.004-inch, which had to be lapped so the new piston
rings would not snag when fitting them.

While the cylinder block was at the machine shop I decided to
sort out the piston ring grooves. While I hate to remove too much
metal, I opted to enlarge the 1/4-inch ring groove to 5/16-inch so
standard size rings would fit. I mounted the piston in the 4-jaw
chuck on the lathe and set it to run true as possible using a dial
indicator. This was not easy because the piston has numerous bumps,
nicks and hollows. I had to use judgment to average these out.
While I could have used a parting tool to widen the ring grooves,
this was likely to flex, so I made small left- and right-hand
cutters out of 1/4-inch high speed steel. I also used a piece of
high speed steel that measured exactly 1/4-inch to use with feeler
gauges to check the width of the machined ring grooves.

Once the ring grooves were cleaned up, I tried the piston in the
sleeved bore. The machine shop proudly told me the bore was now
accurate. This was great, but they had not been able to trial fit
the piston as I had kept it to work on. While it measured less than
4 inches in diameter in places, there were some nicks in it and it
was indeed not round, but oval, so it would not fit.

Back to the lathe, and after some time setting it up again with
a dial gauge, I took a couple of skim cuts so the whole piston to
the skirt was 0.010-inch smaller than the bore. I then turned down
the top land a further 0.0005-inch and the second land 0.0002-inch
as they were likely to get hotter from combustion.

The next step was to set up the cylinder on the pedestal drill
to drill the 1/4-inch hole for the drip oiler feed. I only used
light pressure to avoid splintering the liner. I then cleaned the
area around the hole with medium wet and dry paper.

I thoroughly cleaned the bore and checked the new piston rings
for fit in the bore. To do this, I fit each ring in turn in the
bore and pushed them halfway up the cylinder using the piston. I
then measured the ring gap with feeler gauges. I work on 0.004-inch
clearance for each inch of cylinder diameter. In this case the
required gap was 0.016-inch and only one of the supplied rings
needed a touch with a needle file to bring it to the correct
clearance.

After checking clearances, I fit the rings to the piston by
sliding them over shim stock, into their grooves.

To fit the piston in the cylinder, I used a ring compressor. I
then liberally coated the piston and rings in oil and tightened the
compressor.

Read part two in the next issue - making the water tank and mesh
screen and repairing the magneto.

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